;(function ($) {
  $.fn.typewriter = function () {
    this.each(function () {
      var $ele = $(this),
        str = $ele.html(),
        progress = 0
      $ele.html('')
      var timer = setInterval(function () {
        var current = str.substr(progress, 1)
        if (current == '<') {
          progress = str.indexOf('>', progress) + 1
        } else {
          progress++
        }
        $ele.html(str.substring(0, progress) + (progress & 1 ? '_' : ''))
        if (progress >= str.length) {
          clearInterval(timer)
        }
      }, 75)
    })
    return this
  }
})(jQuery)
